1. Field of Invention
The invention relates to a navigating method for a cell phone with a positioning device and the apparatus thereof. In particular, the invention utilizes the SMS (Short Message Service) to transmit the position coordinates from a GPS.
2. Related Art
With rapid development in the cell phone technology, a new function is added to cell phones every now and then. It has evolved from old black-and-white phones to the current color phones, from monotonic bells to the current musics, the packet transmission for wireless application protocol (WAP) web surfing and general packet radio services (GPRS). The cell phone can even record videos just like the digital video (DV). In spite of its many functions, the most basic two functions of the cell phones have been existent all the time: conversation and transmitting short messages.
According to statistics, the popularity of cell phones in Taiwan has topped the world. Therefore, the cell phone has become an indispensable tool. Each person has at least one cell phone on the average. A valuable function in the cell phone is to allow the user to find out its position from the closest three base stations by trigonometry. Moreover, geographical information such as food, banks, movie theaters, etc can be transmitted to the user. Sometimes, the base station covers a range of as wide as several kilometers. The error can be as large as hundreds of meters. This does not provide the required precision.
Due to recent progress in IC designs and chip productions, manufacturers have developed a global positioning system (GPS) with a small-size chip. Imbedding such a chip in a cell phone enables the cell phone to enjoy the GPS functions. The consumers do not need to spend several hundreds of dollars to carry an additional GPS receiver.